We will have to give Cletis a little leeway. They were advertisements, this board is very busy, and it was late. :punch:
Another thing to consider is a 3/4 ton truck. They are usually work trucks and owners that depend on a truck for work usually take care of them. They also have bigger brakes, more likely to have a 292 six, 8 lug rims, and ride a little rougher. The 292 has as much bottom end torque as a 350 v8. They arn't as desirable as 1/2 tons so you can find one in better shape fr less. If you look for pull offs, you can nice looking late model rims and tires cheap.
All of these trucks have high gearing in the rear axle, especially 3/4 tons, so you'll need an overdrive. Typical rear axle gears are 5.12, 4.56, 4.11. You can replace the rear axle cheaper than a tranny, but you would probably have to have some welding done to mount the new rear axle. If you go with an automatic look for a 700r4 or an early 4L60. One of the considerations with an auto is shifting, most early trucks didn't have automatics. You'll have to have a floor shifter or replace the column with a later model. Manual transmission overdrive are not that common either. A bolt in would be a 3spd with overdrive. I just put an A-833 behind a rebuilt 292 in my 63, 3/4 ton. The A-833 is a 4 spd, fourth being overdrive. It's your choice as to which you prefer.
The links were from craigslist.org. Spend sometime searching craigslist, your only limit is $$$$ and your resourcefulness.
Larry